Gizzard

The gizzard or gizzard ( ventriculus muscularis, also Ventriculus pars muscularis ) is equipped with thick muscles organ in the digestive tract of birds, reptiles, fish, figuratively ( not homologous ) also in invertebrates ( here mostly proventriculus called ). Even with dinosaurs he is suspected. Equipped with hard parts like friction plates, bars or " teeth " and possibly with gastroliths (stomach stones) which serves the crushing of the food and thus made ​​as a kind of substitute for the other groups of animals by chewing ( in the oral cavity by means of teeth ) shredding.

Bird stomach

A separate gizzard is found mainly in the herbivorous ( herbivorous ) birds, especially grain eaters.

In the stomach of the bird gizzard is the second stomach after glandular stomach ( ventriculus glandularis or proventriculus ). The gizzard of birds is lined with gastric mucous membrane (tunica muscosa ), including sitting in a sub- mucosal tissue ( Tela submuscosa ), followed by the actual muscle layer (tunica mascularis ). Its wall consists mainly of smooth muscle. It can be anatomically divided into four separate muscles. The inner surface of the gizzard is of a coarse, yellowish-green layer, the cuticle gastric lined consisting of a solidified gland secretion. It consists of a carbohydrate -protein complex Koilin, with similar properties such as keratin. The cuticle is a friction plate, on which the recorded Magensteinchen ( Gastrolithe grit or called ) grinding the food.

Poultry gizzard is part of the poultry Klein and finds use in the Asian, African, Southern European, Hungarian and Jewish kosher cuisine, including roasted on a salad or in soups.

Pisces

Different lineages of teleosts have developed convergent to each other gizzards. It is in almost all cases to herbivorous ( herbivore ) species, rare to users of dead plant matter ( detritivores ). Gizzards exist with numerous representatives of mullets ( Mugilidae ), surgeonfish ( Acanthuridae ) and nage perch ( Girellidae ) .. At least the mullet use partly Gastrolithe.

Reptiles

Among the living ( extant ) Reptiles only one group has a muscular gizzard: the crocodiles. Although these also absorb stomach stones, a function for the development of food for this was denied and now seems unlikely

Sauropods

The existence of a gizzard in sauropod dinosaurs has been concluded mainly from the discovery of gastroliths, mostly polished pebbles acting in the fossil skeletons. According to recent studies, however, a function of the stomach stones for this purpose appears to be very unlikely. References to the corresponding function for example, offer the Oviraptosaurier Caudipteryx and the theropod Sinornithomimus. This points to an origin of the gizzard in the enlarged core group of birds.